Access door for vacuum type filter boxes



w. w. HEWITT 5 DOOR FOR VACUUM TYPE FILTER BOXES I I 2 Skieets-Sheqt 1 July 16, 1957 ACCES Filed June 29, 1955 ATTORNEYS w. w. HEWITT ACCESS DOOR FOR VACUUM TYPE FILTER BOXES Filed June 29, 1955 July 16, 1 957 2 Sheets-Stage: 2

. INVENTOR, Woweow N NE W/TT- ATTORNEYS ACCESS DOOR FOR VACUUM TYPE FILTER BOXES Woodrow W. Hewitt, Charlotte, N. C., assignor to Spmsavac Corporation, Charlotte, N. C., a corporation of North Carolina Application June 29, 1955, Serial No. 518,710

8 Claims. (Cl. 18337) This invention relates to vacuum type filter boxes of the type commonly employed in conjunction with pneumat1c clearing systems for spinning, roving and drawing frames and, more particularly to a novel type of door whereby access to the filter box may be gained without disturbing the vacuum within the box.

Pneumatic clearing systems have proven highly successful in removing lint from the immediate vicinity of spinning frames and the like, but much difliculty has heretofore been encountered in the ultimate disposition of the lint from the pneumatic system after it has been collected at a point remote from the spinning frames. One manner of collecting the lint is to provide a vacuum type .filter box at a point remote from the spinning frames attached to collect the lint against a screen or similar foraminated material. Upon the screen becoming clogged with an accumulation of lint it is necessary to remove the accumulation of lint to permit proper operation of the pneumatic system.

This removal of accumulations of lint from the screen has heretofore been accomplished by opening a door in the filter box and manually removing lint. This has proven disadvantageous in that, upon the filter box door being open, the suction within the pneumatic system is broken and considerable time is thereafter lost in creating suflicient suction to remove the lint from the spinning frames.

It is therefore an object of this invention to provide a novel door for filter boxes by means of which access to the interior of the filter box may be had to remove accumulations of lint without materially disturbing the vacuum within the pneumatic system.

It is another object of this invention to provide improved means for gaining access to the interior of a vacu um type filter box having an opening therein which is normally closed by a rigid door hingedly connected to the filter box, and which opening is further closed by means of another inner door formed of flexible nonporous web material whereby the opening may be substantially sealed to maintain a vacuum within the box upon the outer rigid door being opened. The inner door is slotted to permit ones fingers to pass therethrough and, thus, the slot may be enlarged for a persons arm to pass therethrough. Of course, when the persons arm is withdrawn from the slot, the flexibility of the doors again reduces the slot to its original size.

Some of the objects of the invention having been stated, other objects will appear as the description proceeds, when taken in connection with the accompanying drawings, in which- Figure 1 is a side elevation of a spinning frame, with parts broken away, and showing a pneumatic control system including a vacuum type filter box associated with the spinning frame.

Figure 2 is an end elevation looking at the right-hand side of Figure l;

Figure 3 is an enlarged vertical sectional view showing States Patent the improved filter box door and taken substantially along line 3-3 in Figure 1;

Figure 4 is an enlarged sectional plan view taken along the line 4-4 in Figure 1, but omitting the suction or blower unit;

Figure 5 is an enlarged vertical sectional view taken along the line 5-5 in Figure 2;

Figure 6 is an enlarged partially exploded isometric view of the filter box door, showing the rigid imperforate door in open position;

Figure 7 is a sectional 7-7 in Figure 6.

Referring more specifically to the drawings, while the present improvement is not limited thereto, it is shown in association with a spinning frame or machine including a head-end frame member 10 and a foot-end frame member 11 which are connected to opposite ends of grits or roll stand supports 12, only one of which is shown in Figure l. The girt 12 supports a plurality of roll stands 13 which, in turn, support conventional drawing rolls or drafting rolls 14. Only the lower or bottom drawing rolls are shown in Fig. 1, these drawing rolls being provided with a plurality of longitudinally spaced bosses 15 thereon.

The frame members or girts 12 also support a creel 16 which carries a plurality of yarn packages, spools or bobbins 17 from whence the yarn is drawing and which passes between and is attenuated by the drawing rolls 14. From the drawing rolls 14, the strands of yarn are wound onto bobbins, not shown, in the usual manner. The machine in Figure 1 also includes a tape driving cylinder 20 which is journaled on the end frame members 10, 11 and has a pulley 21 fixed on one end thereof, connected by belt 22 to a pulley 23 fixed on the shaft of an electric motor 24.

With the exception of the improved filter box access door, the pneumatic clearing system associated with the spinning machine shown in Figures 1 and 2 may be of conventional or any desired construction and is broadly designated at 25. Extending longitudinally of the machine and below the level of the roll stand support 12 is an elongated suctionpipe or duct 26 having a plurality of relatively small branch pipes 27 extending therefrom, only one of which is shown in Figure l. The other ends of these branch pipes 27 are communicatively connected to elongated tubular suction heads 28 which are suitably supported immediately below the bottom rolls of the spinning machine and which have a plurality of slots 28a in their upper surfaces coinciding with and preferably being substantially the same length as the bosses 15 of the drawing rolls 14.

One end of the duct or suction pipe 26 is closed at 29 and its other end extends beyond the foot-end frame member 11, then curves upwardly and is communicatively connected to the bottom wall 38 of a filter box broadly designated at 30. The filter box 30 is suitably supported, as by angle brackets 31 suitably secured to the foot-end frame member 11. In addition to the bottom Wall 38, the filter box 30 also includes a top wall 33 and side walls 34, 35, 36 and 37. The top wall 33 is provided with a suitable air discharge opening 39 (Figure 5).

A suction device, impeller or blower 42 is mounted in plan view taken along the line a tubular blower housing 43 within the filter box 30, the

3 of the chambers, in which the fan or blower unit 42, 43 is disposed may be termed as a suction chamber and is broadly designated at 46. The other chamber may be termed'as a fiber collection chamber and is broadly designated at 47.

'It will be noted that the suction pipe communicates 'Wiih the chamber 47 and the screen 45 spans the distance between the walls 33, 38, 36 and 37. Any desired type of impeller, suction device or blower unit may be employed to serve the purpose of the blower unit including elements 42, 43. However, in the interest of minimizing the space required for such a device, it is preferable that an industrial fan of a type distributed by Joy Manufacturing Company, Oliver Building, Pittsburgh, Pennsylvania, under the trade name Axivane, be used for this purpose.

Whenever the impeller or suction device 42 is activated, suction is created in the filter box 30 and in the suction pipes 26, 27 and 28 which comprises the pneumatic clearing system 25 so that air is drawn into the openings or slots 28a in the intake suction heads or pipes 28. It is apparent that air entering the openings 28a will carry with it any lint and fly which would otherwise tend to accumulate on the bosses of the drafting rolls 14. The suction in the pneumatic clearing system causes any lint drawn through the openings 28a in the intake suction pipe 28 to accumulate against that surface of the screen adjacent the suction pipe 22 and chamber 47.

It is necessary to periodically remove lint and other matter which has accumulated on the screen 45 and in chamber 47 in order to prevent the screen from becoming clogged which would reduce the efficiency of the pneumatic clearing system 25. This removal of lint is normally accomplished manually and the provision of means for gaining access to the chamber 47 without materially reducing the vacuum pressure in the pneumatic clearing system 25 is an important feature of this invention.

To this end, the side walls 36, 37 are provided with respective openings 50, communicating with chamber 47. The openings 50, 50' in the side walls 36, 37 are closable by outer doors 51, 51' hingedly connected to the side walls 36, 37. The openings 50, 50 are sufficiently large to permit a mans arms to be inserted within the filter box to remove lint from the screen 45 and chamber 47 and, in order to enable the operator to reach the upper and lower portions of the'screen 45, the openings 50, 50 are necessarily elongated in a vertical direction. It is apparent that, upon the doors 51, 51' being opened, the vacuum within the pneumatic clearing system will be broken by permitting a large amount of air to enter the open doors 51, 51. This has heretofore proven undesirable in that much time is lost in building up a suflicient vacuum within the pneumatic clearing system to effectively remove lint from the vicinityof the spinning frame.

In order to prevent the vaccum from being broken when the doors 51, 51' are opened, this invention is embodied in an inner door for each access opening 50, 56 which permits access to the interior of the filter box 30 without materially reducing the vacuum pressure. As most clearly shown in Figures 3, 4, 6 and 7, the edges of each opening 50, 50 are formed by L-shaped frame portions 52. This L-shaped frame provides a recess in each wall 36, 37 in which a gasket 53 is preferably mounted in order to seal each opening 50, 59 when the respective outer doors 51, 51' are closed. A rectangular frame broadly designated at 54- comprises identical skeleton frame sections 55, 56 and is connected to the inner surfaces of the L-shaped portions 52 as by screws or rivets 57.

The frame 54 serves to confine a sheet of fabric or other pliable Web material 60 against the opening 50, it being noted in Figure 6 that the edges of the fabric 60 are confined between the frame sections 55, 56. The fabric 66 forms a flexible inner door which is slotted or slitted longitudinally thereof at its medial portion, said slit ter minating in spaced relation to the upper and lower edges of the fabric 60. It is thus seen in Figure 6 that the medial portion of the fabric 60 is divided into portion-s 60a and 6% by the slit. The edges of the fabric 60a and 60b adjacent the slit are turned upon themselves and stitched or otherwise fastened, as at 61, to form tubular portions 62, in each of which a coil spring 63 is positioned. The springs 63 are of slightly lesser length than the tubular portions 62 and are not anchored at either end, the upper and lower ends of the tubular portions 62 being closed by stitching or other fastening means 64 extending transversely at each end of the tubular portions 62 as shown in Figure 6.

The upper and lower portions of the fabric 60 are pleated as at 65, 66, said pleats being maintained in the fabric by the frame sections and 56. The pleats 65, 66 provide additional flexibility for the inner door 60.

The slot 67 is of suflicient width to permit an operators fingers to be inserted therethrough and the flexibility of the door 66 permits the operator to reach all portions of the screen 45 without opening the door sufficiently to disturb the vacuum within the filter box and the pneumatic clearing system. In fact, an operators arm will nearly close the opening 67 when thrust therethrough and the springs serve to return the inner door 60 to its original position when a persons arm is withdrawn therefrom.

The fabric form which the inner door 60 is made is preferably impregnated with rubber or a synthetic equivalent material to insure that the fabric is airtight and non-porous.

It is thus seen that there is provided a filter box door which permits access to the interior of the box without materially disturbing the vacuum pressure there- When the proximal edges of web portions 60a, 6012 are turned upon themselves to form the tubular portions 62, a relatively narrow slot 67 is formed between web portions 60a, 60b and the pleated portions 65, 66. The size of slot 67 relative to the size of opening 50 is such that the door 51 may remain open indefinitely without materially lowering the negative pressure in the cleaning system 25. For example, the door 51 may be eight inches wide and 14 inches high and the opening 67 need not exceed two inches in width and eight inches in height. The springs 63 may be as little as one-eighth of an inch in diameter.

In the drawings and specification there has been set forth a preferred embodiment of the invention and although specific terms are employed, they are used in a generic and descriptive sense only, and not for purposes of limitation, the scope of the invention being defined in the claims.

I claim:

1. In a pneumatic cleaning system for textile machinery, said system having a filter box, a screen disposed in the filter box and separating the filter box into a lintcollecting compartment and a suction compartment, means for creating suction currents in the suction compartment, a suction pipe connected to the filter box for communication with the lint-collecting compartment and at least one of the side walls of said filter box having an access opening therein; the combination of a double closure for said opening including a rigid outer closure member and a flexible inner closure member for said opening, said flexible inner closure member comprising a framework of a size substantially the same as said opening, a pliable web material carried by said framework, said pliable web material including an upper pleated portion and a lower pleated portion spaced from the upper pleated portion, the central portion of said web material having a vertically extending slot therein terminating at its upper and lower ends at the respective upper and lower pleated portions and defining a pair of horizontally spaced flat portions on opposite sides of the slot and extending between the upper and lower pleated portions, the proximal edges of said side portions being rolled upon themselves and attached to said opposite side portions to form tubular portions along the proximal edges of said opposite side portions, a coil spring dismaterial are positioned, and means clampingly securing the inner and outer frames together and securing the inner and outer frames to the corresponding wall of the filter box.

3. A closure for openings in a filter box of the character used in a pneumatic cleaning system wherein the filter box is provided with means for creating suction currents therein and wherein one end of a suction pipe is communicatively connected to the filter box; said closure comprising an outer rigid closure member movable relative to said box and a flexible inner closure member, said flexible inner closure member comprising a substantially rectangular sheet of pliable web material having a longitudinally extending slot in its central portion, at least one end of said slot being spaced from the corresponding end of the web material, said corresponding end being provided with a plurality of transverse pleats, the proximal edges of the portions of the sheet defining said slot being hemmed to form tubular portions at the proximal edges thereof, and a coil spring mounted within each of said hemmed portions of the web material, thus tending to maintain the flat form of the web material and being yieldable to permit ones hand to be thrust through the slot in the sheet of web material.

4. A structure according to claim 3 wherein said sheet is supported by a frameworkcomprising an inner frame and an outer frame between which corresponding edge portions of the sheet are positioned, and means clampingly securing the inner and outer frames together and securing the inner and outer frames to the corresponding wall of the filter box.

5. In a pneumatic cleaning system for textile machinery, said system having a filter box, a screen disposed in the filter box and separating the filter box into a lintcollecting compartment and a suction compartment, means for creating suction currents in the suction compartment, a suction pipe connected to the filter box for communication with the lint-collecting compartment and at least one of the walls of said filter box having a substantially rectangular access opening therein; the combination of a double closure for said opening including an outer closure member and a flexible inner closure member for said opening, said flexible inner closure member comprising a framework of a size substantially the same as said opening, a pliable web material carried by said framework, said pliable web material being formed with a pleated portion on each end thereof, a relatively narrow longitudinally extending slot in the central portion of the web material terminating at its ends at the respective pleated portions and defining a pair of transversely spaced flat portions on opposite sides of the slot extending between the pleated portions, the proximal edges of said fiat portions being rolled upon themselves and attached to the flat side portions to form tubular portions along the proximal edges of said flat side portions, a coil spring disposed in each of said tubular portions, and means closing opposite ends of each of the tubular portions.

6. In a pneumatic cleaning system for textile machinery, said system having a filter box, a screen disposed in the filter box and separating the filter box into a lintcollecting compartment and a suction compartment,

means for creating suction currents in the suction compartment, a suction pipe connected to the filter box for communication with the lint-collecting compartment and at least one of the walls of said filter box having a substantially rectangular access opening therein; the combination of a flexible closure member for said opening comprising a substantially rectangular framework fixed to said wall and encompassing said opening, a pliable web material carried by said framework, said pliable web material including at least one pleated portion, a longitudinally extending slot in the central portion of the web material terminating at one end adjacent the pleated portion and defining a pair of transversely spaced fiat portions on opposite sides of the slot, the proximal edges of said fiat side portions being rolled upon themselves and attached to said flat side portions to form tubular portions along the proximal edges of said side portions, a coil spring disposed in each of said tubular portions, and means closing opposite ends of each of the tubular portions.

7. A closure for openings in a filter box of the character used in a pneumatic system wherein the filter box is provided with means for creating suction currents therein and wherein one end of a suction pipe is communicatively connected to the filter box; said closure comprising an outer closure member and an inner flexible closure member, said flexible inner closure member comprising a substantially rectangular sheet of pliable web material having a longitudinally extending slot in its central portion, at least one end of said slot being spaced from the corresponding end of the sheet, said corresponding end portion being provided with a plurality of transverse pleats, the proximal portions of the portions of the sheet defining said slot being hemmed to form tubular portions at the proximal edges thereof, and an elongated flexible member mounted within each of said hemmed portions of the web material, thus tending to maintain the flat form of the web material and being yieldable to permit ones hand to be thrust through the slot in the sheet of web material.

8. In a pneumatic cleaning system for spinning frame and the like including a suction pipe and a filter box, a lint-collecting screen disposed within said filter box and dividing said filter box into two compartments, said suction pipe being communicatively connected to one of said compartments and an impeller mounted in the other of said compartments for creating a suction within said system, at least one wall of the compartment with which said suction pipe is communicatively connected having an opening therein, said opening communicating with the atmosphere and being provided to permit removal of lint which has accumulated on said lint collecting screen; the combination of a flexible door for said opening whereby lint may be removed from the lintcollecting screen without adversely disturbing the suction within said system, said door comprising a frame enclosing said opening and fixed to .the filter box adjacent the edges of said opening, a sheet of impervious fabric mounted in said frame and extending across said opening, a plurality of transverse pleats extending across each end of said sheet, the medial portion of said sheet being of substantially planar configuration, a longitudinally extending slit in said sheet, and a pair of elongated resin members secured to the edges of said sheet adjacent opposite sides of said slit.

References Cited in the file of this patent UNITED STATES PATENTS 1,123,564 Marx Ian. 5, 1915 1,663,819 Shaft Mar. 27, 1928 2,560,661 Poovey July 17, 1951 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PatentNo. 2,799,356 July 16, 1957 Woodrow W. Hewitt It is hereby certified that error appears .in the printed specification of the above numbered patent requiring correction and that the and Letters Patent should read as corrected below.

Column 6, line 65, for "resin" read resilient Signed and sealed this 20th day of August 1957.

( L) Attest:

KARL H. AEINE ROBERT C. WATSON Attesting Officer Conmissioner of Patents 

